next week i am getting motive performance gears put in my truck (good price good warranty through ford dealer) and i am debating a limited slip. but i have several questions and thoughts...

is it worth it? their not cheap and my truck is mainly used as daily transportation but does see a little off road/recovery vehicle use. ive been through lots of snow and mud with very little issues (stuck once, high centered on ice)

a lot of me thinks its going to be like the 5.4 vs 4.6 debate. the limited slip has more to offer for performance but costs more, most of the time is not needed, and has higher maintenance costs.

if i DO get a limited slip, do i need a 28 spline or a 31?

please don't tell me to get lockers. i don't want to spend a lot of money and it would be overkill for my use.

right now i'm thinking about keeping open diffs and upgrading someday in the future. most likely the truck will be with me till its wrecked beyond repair.

please discuss, thanks!

 

I think every truck should have LS. My first few trucks did not and I got plenty of one wheel peel. My last two have had it, one 2wd and my current 4wd. I would be hard pressed to buy a truck again without LS. Its so much more stable and usable.

 

i like the LS, my last trucks wore out tho and sucked. i know you said no to lockers, but what about an air locker for the rear? be better than LS offroad, and you can turn it off while on the road, and on snowy roads it might be nice to have both rear tires spinning constantly. i dont know much about air lockers, im still reading up on them and learning, just thought id throw that out there if you hadn't looked into them seems like they give the best of both worlds

 

If you have the 4.6 then you have an 8.8 rear axle with 31 spline axles
the 5.4's get the 9.75 rear with 34 splines.

The front axle on 4x4's all get the 8.8 with I believe 28 splines.

 

thats my point exactly, i'm starting to think it wont be worth $500 to put a limited slip in that i don't NEED just to have it wear out. i questioned getting a 4.6 but it has been plenty sufficient and i dont suffer from any of the "issues" out there (not a slam on you 5.4 guys, i would like one, just dont need it)

i said no to lockers now... someday down the road i would like to get a bmw and keep the truck around for a work/play vehicle and then i may do an air locker or something of the like at that time.

 

thats what i thought, but everyone seemed clueless. thanks!

 

the 4.6 is a beast. i shock alot of people when i keep up or beat their 5.4's

ill hopefully have air lockers in the next year on my fj40 so i can give a good and honest review on them.

 

what's the break in procedure on gears?

 

If you ever have plans to upgrade the rear differential, why wouldn't you do it with the gear install? It's only going to cost you more later. The aftermarket units are not as easy to wear as you might think. Keep your tires inflated to the same pressure and it should last 100,000 miles or more. The Detriot TrueTrac doesn't have clutches to wear out.

 

Usually it is just to drive "easy" for the first 500 miles, and then do an oil change / inspection, and you all set.

im jealous..... i want some 4.56's........

 

would 500 mi on the interstate be a bad idea?

i'm jealous of your lift so were even...

 

i'm just not sold that its worth the $500+, my open rear does well when things get deep. i need gears for my transmissions sake...

 

I know it is easy to spend someone else's money, but I installed a TrueTrac in my '08 Screw just before winter. It transformed my truck into a completely different animal. I thought it handled the snow pretty well before, now the snow is, well, a non issue. Can't recommend it more highly.

HYPO

 

It'll be 750+ if you decide to upgrade later, is the point I'm making. Only you can decide if it's worth it to you.

 

i understand your point. i think i am going to stay open. ive only gotten stuck once in my truck and i think a winch would have been the only thing that could have helped me. open rears are just more predictable for daily driving and much cheaper.